Maitland-Niles looked set to be a regular in Unai Emery’s first-team squad this season following his promising displays last term.

However, the 20-year-old could now be set for up to two months of rehabilitation after suffering an injury in the Gunners’ opening Premier League defeat to Manchester City.

The versatile midfielder, who was playing at left-back on Sunday, hurt his leg in a challenge with Kyle Walker and despite trying to play on, was eventually substituted for Stephan Lichtsteiner after 35 minutes.

Arsenal lost 2-0 against champions City in Emery's first competitive game in charge.

Meanwhile, Charlton Athletic have confirmed they have signed Arsenal ace Krystian Bielik on a season-long loan.

The 20-year-old, who has made two senior appearances for the Gunners, has become Lee Bowyer’s fourth signing of the summer at the League One club.

He said: “It’s a big stadium, a massive stadium, I didn’t know [how big the stadium was]. It looks good and I’m looking forward to playing at this stadium and doing my best here.

“I want to show everyone that I can play football. It’s a good opportunity for me to play here because I know people are going to watch me and I’m under pressure. That’s what I like, I want to do my best.”

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Arsenal ace Krystian Bielik has joined Charlton Athletic on a season-long loan

Addicks boss Bowyer added: “He is someone that can protect the back four. He’s good on the ball, strong and he’s someone that can fill in at centre-half as well.

“He’s obviously good on the ball, you don’t play for Arsenal unless you can play, so I know he’s going to be another great addition to the squad.

“I couldn’t tell you how many phone calls [Head of Recruitment] Steve Gallen made to Arsenal to try and get this one over the line. It’s been going on for a while now, so we’re delighted to get him here.

“Obviously, there were other clubs involved trying to get him, like all the others that we’re trying to bring in so he’s no exception but that’s what happens when you are trying to bring in good players.”